Warning flag assembly



FIG. 1 is a front perspective view of a warning flag assembly showing my new design;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a rear view thereof; and,

FIG. 5 is a front view thereof.

In the drawings, the lumber and attachment hardware shown in broken lines form no part of the claim. 

The ornamental design for a warning flag assembly, as shown and described. 